The same car suddenly has two different CO2 values, why is this?

The new Worldwide Harmonised Light Vehicle Test Procedure (WLTP) is a new and more robust test cycle for cars, and therefore has higher (but more realistic) CO2 and fuel consumption values.

Before September 2017, all cars at dealerships had CO2 values based on the old NEDC test (the New European Driving Cycle).

During the period of transition from NEDC to WLTP that started in September 2017, cars approved before then will continue to have CO2 values as measured under the NEDC test only.

However, when a new car type is certified under WLTP after September 2017, its official vehicle documents (the Certificate of Conformity) will have CO2 emission values from both the new lab test as well as the old one.

From September 2018, all new cars must have WLTP-CO2 values

This means that after September 2017, when the switch from the NEDC to WLTP is being made, one might come across two different values for the same car. This risks being quite confusing, making it difficult to compare cars.

A very important issue therefore is how WLTP will be integrated in car labelling and other consumer information.

When you use our website, cookies are placed on your device. By clicking on 'Agree', you indicate that you have read all information about our use of cookies and that you explicitly agree to the use as set out in our cookie policy.